Nearly One-Third of Trauma Patients Given More Than 50 Units of Blood Survive

Thirty-one percent of trauma patients who received more than 50 units of whole blood or components during the first four hours of treatment survived, compared with 79% of those who received 50 units or less, according to new findings in the Journal of Trauma and Acute Care Surgery.

Investigators at UT Health Houston led the study and were not able to determine a threshold of whole blood or component units at which it may be futile to administer additional units in adult trauma patients. The findings, they suggest, confirm that continuing blood transfusions when treating trauma patients with severe blood loss can save lives.

“When looking at our experience here locally, there really isn’t a blood transfusion number where you should stop,” senior author Bryan Cotton, MD, said in a news release. “There are plenty of lab markers and plenty of physiology, blood pressure, and vital sign monitors where you can say, ‘We’re not getting this patient back. This patient is absolutely not going to survive.’ But by using and looking at just blood transfusion numbers, we did not really find a point where there are no survivors.”

The findings lend clarity to transfusion thresholds at which physicians should stop giving blood products to a trauma patient. With blood products in short supply during the COVID-19 pandemic, the researchers were prompted to examine whether there is a threshold at which it is futile to give trauma patients additional blood or components.

Cotton said that during the COVID-19 pandemic, centers around the world began running low on blood supplies. Because severely injured patients require a great deal of resources, including blood products, researchers examined whether there is a transfusion threshold where physicians should stop giving a trauma patient blood, as well as the effect of whole blood, instead of blood components, on mortality.

The study included 2,299 adult trauma patients who received emergency-release blood products prehospital or in the emergency department. Of these, 2,043 patients received 50 units or fewer and 256 patients received more than 50 units. Investigators defined “total blood products” as total RBC, plasma and whole blood prior to arriving at the hospital and in the first 4 hours after arrival. Fifty units in the first 4 hours has previously been defined as a transfusion threshold.

The 1,291 patients who received whole blood had 43% improved odds of survival compared with the 1,008 patients who received only components. In addition, patients receiving whole blood had shorter hospital and intensive care unit stays and were not on ventilation as long compared with those who received components only. However, there were also no differences in survival between these groups.